OASEARCH: Modelo de aplicación basado en web semántica para la búsqueda de objetos de aprendizaje mediante perfilado de consultas

Uno de los aspectos que determina la calidad de un Sistema Educativo Basado en la Web es la manera en que este proporciona a los estudiantes los objetos de aprendizaje que mejor se adaptan a sus condiciones específicas -- Es por lo anterior que se hace necesario contar con mecanismos de búsqueda para estos objetos que puedan ser usados fácilmente por la aplicación o por los usuarios de la misma y que entreguen los resultados más relevantes posibles en un contexto determinado -- Múltiples mecanismos se han propuesto para la búsqueda de recursos digitales en la web -- El enfoque fundamental de recuperación de la información ha sido utilizado por muchos años con bastante éxito pero con el advenimiento de las tecnologías que componen lo que se conoce como La Web Semántica es posible definir nuevas representaciones para los datos que permiten obtener una mayor precisión y relevancia de los resultados obtenidos -- El presente documento presenta un nuevo enfoque para la construcción de motores de búsqueda para objetos de aprendizaje basado en La Web Semántica que se apoya en la definición previa o perfilado de consultas de una manera desacoplada de la aplicación -- Con este enfoque es posible construir Conceptos de Búsqueda que son especificados en una Ontología de Dominio de tal manera que luego puede ser utilizada por la aplicación para entregar sus resultados en un entorno distribuido de repositorios RDF que se basen en el estándar LOM para la descripción de metadato

Numerical evaluation of the Green's functions for arbitrarily shaped cylindrical enclosures and their optimization by a new spatial images method

IIn this paper, a spatial image technique is used to efficiently calculate the mixed potential Green’s functions associated with electric sources, when they are placed inside arbitrarily shaped cylindrical cavities. The technique is based on placing electric dipole images and charges outside the cavity region. Their strength and orientation are thencalculated by imposing the appropriate boundary conditions for the fields at discrete points on the metallic wall. A method for the assessment of the potentials accuracy is proposed, and several optimization techniques are presented. Three cavities are analyzed to demonstrate the usefulness of the techniques. The cutoff frequencies and potentials patterns are compared to those obtained by a standard finite elements technique, showing excellent agreement. Finally, a band-pass filter based on coupled lines is analyzed, demonstrating the practical value of the technique.This work has been developed with support from the Spanish National Project (CICYT) with reference TEC2004-04313-C02-02/TCM, and the Regional Seneca Project with reference 02972/PI/0

Efficient Calculation of the Green's Functions for Multilayered Shielded Cavities with Right Isosceles-Triangular Cross-Section

An efficient calculation of the Green’s functions inside multilayered shielded cavities with right isosceles-triangular cross-section is presented. The method is entirely developed in the spatial domain, and it is based on image theory. The idea is to use the spatial-domain Green’s functions inside a multilayered shielded square box, in order to accurately obtain the Green’s functions for the right isosceles-triangular cavity. Image theory is then used to enforce the boundary conditions along the non-equal side of the triangle. It is shown that the new algorithm is very robust, with limited computational effort. Resonance frequencies and potential patterns of a triangular cavity have been calculated and compared with those obtained by other techniques, showing very good agreement. Finally, a transversal filter inside a multilayered triangular-shaped cavity is designed, manufactured and tested using the developed technique.This work was partially supported by the Spanish Ministry of Education and Science under Grant FPU-AP2006-015 and with the Project TEC2007-67630-C03-02

Las fresnedas trasmochadas del piedemonte del Sistema Central en Madrid (España): cambios y usos actuales

Se pretende analizar y comparar la evolución de los aprovechamientos de diferentes fresnedas trasmochadas de Fraxinus angustifolia en el piedemonte de la Sierra de Guadarrama (Madrid, España). En este sector de la Península Ibérica el espacio forestal ha sufrido intensas transformaciones que han modificado la superficie de la masa arbolada. En ocasiones las variaciones no han afectado a la extensión superficial arbolada sino a su funcionalidad productiva. Este es el caso de las especies ubicadas en los sectores más productivos de fosas y depresiones del centro peninsular. Los fresnos han sido y siguen siendo formaciones silvopratenses productivas que, en el caso de Madrid, constituyen uno de los paisajes de mayor interés cultural y natural de la Península, pese a que la presión urbanística, el productivismo intensivo y la desaparición de la ganadería tradicional y de los canales de trasmisión de la cultura silvoganadera, hayan generado una disminución progresiva de las prácticas productivas tradicionales. En este trabajo realizamos una aproximación a la evolución histórica de la funcionalidad de las fresnedas mediante fuentes históricas que nos remontan a Ordenanzas de siglos pretéritos y enlazan, en un intento de comparación, con las fuentes digitales disponibles desde mediados del siglo XX. El objetivo final estriba en reconocer el interés que implica el mantenimiento de las fresnedas como un paisaje tradicional productivoThe aim of this work is to analyze and compare the evolution of the different harvested fresnedas of Fraxinus angustifolia in the piedmont of the Sierra de Guadarrama (Madrid, Spain). In this sector of the Iberian Peninsula the forest space has undergone intense transformations that have modified the surface of the wooded mass. Sometimes the variations have not affected the surface extension of the tree but its productive functionality. This is the case of species located in the most productive areas of pits and depressions of the peninsular center. The ash trees have been and continue to be productive silvopratensian formations that, in the case of Madrid, constitute one of the landscapes of greater cultural and natural interest of the Peninsula, despite the fact that urban pressure, intensive productivism and the disappearance of traditional livestock And of the transmission channels of silvoganadera culture, have generated a progressive decrease of the traditional productive practices. In this work we make an approximation to the historical evolution of the functionality of the fresnedas through historical sources that go back to Ordinances of previous centuries and link, in an attempt of comparison, with the digital sources available since the middle of the 20th century. The ultimate goal is to recognize the interest in maintaining fresnedas as a traditional productive landscap

A new neural network technique for the design of multilayered microwave shielded bandpass filters

In this work, we propose a novel technique based on neural networks, for the design of microwave filters in shielded printed technology. The technique uses radial basis function neural networks to represent the non linear relations between the quality factors and coupling coefficients, with the geometrical dimensions of the resonators. The radial basis function neural networks are employed for the first time in the design task of shielded printed filters, and permit a fast and precise operation with only a limited set of training data. Thanks to a new cascade configuration, a set of two neural networks provide the dimensions of the complete filter in a fast and accurate way. To improve the calculation of the geometrical dimensions, the neural networks can take as inputs both electrical parameters and physical dimensions computed by other neural networks. The neural network technique is combined with gradient based optimization methods to further improve the response of the filters. Results are presented to demonstrate the usefulness of the proposed technique for the design of practical microwave printed coupled line and hairpin filters

A New Way of Teaching Ancient History: The Case of the Bachelor’s of Education at the University of Seville

Fernando Lozano Gómez, Alfonso Álvarez-Ossorio Rivas, and Victor Sánchez Domínguez assess the conclusions of several successive research projects on teaching innovation funded by the University of Seville. Members of the Department of Ancient History developed these projects that are indebted to game based learning. The main goal was to present History in all its complexity, without simple explanations, and to improve the student’s general knowledge of the subject by promoting autonomous learning. The paper presents the new teaching materials created by the members of the project. These include an open access handbook with specific teaching tools, instructions for autonomous learning through historical role-play, and the use of timeline playing cards in the university classroom for learning History

Application of the high-gain substrate-superstrate configuration to dielectric leaky-wave antennas

The high-gain substrate-superstrate configuration, which was proposed to increase the gain in printed circuit antennas, is applied to dielectric leaky-wave antennas (LWAs) to improve its frequency response. Analysis of a slitted suspended dielectric rectangular waveguide is carried out using a full-wave method. It is proved that the minimum values of the leakage constant of the leaky-wave mode for the suspended configuration are related to the high-gain resonance conditions. Moreover, it is found that the suspended LWA exhibits very small beamwidth variations in a large frequency bandwidth. It is well-known that inhomogeneous filled LWAs suffer from variation of beamwidth as the angle of maximum radiation is scanned with frequency. The proposed topology can be adjusted so that a flat response of the beamwidth can be obtained in a large frequency band, while maintaining the frequency-scanning behavior of the LWA.This work was supported by Spanish National Projects ESP2001-4546-PE and TIC2000-0591- C03-03, by Regional Seneca Projects 2002 PB/4/FS/02 and PMPDI-UPCT- 2004, and by the EPSON-Ibérica Foundation

Analysis and design of periodic leaky-wave antennas for the millimeter waveband in hybrid waveguide-planar technology

This work presents a full-wave integral equation approach specifically conceived for the analysis and design of laterally-shielded rectangular dielectric waveguides, periodically loaded with planar perturbations of rectangular shape. This type of open periodic waveguide supports the propagation of leaky-wave modes, which can be used to build leaky-wave antennas which exhibit many desirable features for millimeter waveband applications. The particularities of the leaky-mode analysis theory are described in this paper, and comparisons with other methods are presented for validation purposes. Using this leaky-mode analysis method, a novel periodic leaky-wave antenna is presented and designed. This novel antenna shows some important improvements with respect to the features of previously proposed antennas. The results of the designed radiation patterns are validated with three-dimensional electromagnetic analysis using commercial software.This work was supported by Spanish National projects ESP2001-4546-PE and TEC2004-04313-C02-02/TCM and Regional Séneca projects 2002 PB/4/FS/02. The authors would like to thank the EPSON-Ibérica Foundation for its stimulating support. and PMPDI-UPCT-2004. The authors would like to thank the EPSON-Ibérica Foundation for its stimulating support

CONCIENS: organizational awareness in real-time strategy games

The implementation of AI in commercial games is usually based on low level designs that makes the control predictable, unadaptive, and non reusable. Recent algorithms such as HTN or GOAP prove that higher levels of abstraction can be applied for better performance. We propose that approaches based on Organizational Theory can help providing a sound alternative for these implementations. In this paper we present CONCIENS, an integration of the ALIVE organizational framework into commercial games. We introduce a proof-of-concept implementation based on the integration to Warcraft III.Peer ReviewedPostprint (author’s final draft

Linking Neutrosophic AHP and Neutrosophic Social Choice Theory for Group Decision Making

Abstract. Analytic Hierarchy Process (AHP) is a decision-making technique that has been widely studied and developed by the scientific community. The interest in this tool is because it combines scientific rigor with the simplicity of its application. Additionally, it has been extended to uncertainty frameworks, such as fuzzy and neutrosophic frameworks. This paper aims to define a new method called NAHP+NSC, where the Neutrosophic Analytic Hierarchy Process (NAHP) is combined with the recently introduced Neutrosophic Social Choice (NSC) theory. Neutrosophy incorporates indeterminacy to both the AHP technique and the SC theory, which is an intrinsic condition of any decision-making process. On the other hand, it is possible to count on a group of experts to carry out the NAHP evaluations, where the chosen alternative is the one with the highest votes. Experts are divided into kind of homogeneous sub-groups called Interest Groups (IG), where each IG conjointly evaluates the proposed alternatives, and then tools of NSC are used for choosing the best alternative. The contribution of this new method is that evaluations and results are more accurate when indeterminacy is incorporated